Vehicle security device with electronic use authorization coding

US5619573A · kind A · utility

Assignee

• Mercedes-Benz Group AG · DE

Inventors

• Horst Brinkmeyer · Waiblingen, DE
• Michael Daiss · Echterdingen, DE
• Gunter Schwegler · Waiblingen, DE
• Bertolt Kruger · Bonn, DE

Key dates

• Filing date: Apr 3, 1995
• Grant date: Apr 8, 1997
• Expiry date: Apr 3, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L2209/84
• WIPO field: Control
• WIPO sector: Instruments

Abstract

The invention provides a vehicle security device with an electronic use-authorization coding arrangement for identifying authorized access to the vehicle. The vehicle security device utilizes an encryption method which operates on the basis of a one-way function, so that it is only absolutely necessary to store secret code information at the key end, specifically in the form of different inverse images of a one-way function. Only the one-way function values corresponding to these inverse images need be present at the vehicle end, a reading-out of which does not permit unauthorized manufacture of a copied key because of the virtual irreversibility of the one-way function.